How Maritime Realism Explains Japanese Security Policy

The ongoing global health crisis has placed economic resilience at the center stage of national strategy. At the same time, Japan’s own economic wellbeing has been jeopardized by China’s maritime expansion in the East and South China Seas which threatens not only Japan’s territorial integrity but also the freedom of navigation which is vital for a trading nation that relies on free and open access of the seas. As a leading expert notes, China’s recent behavior in the East China Sea in the waters adjacent to the Senkaku/Diaoyu Islands demonstrates how Beijing has intensified pressure on Japan’s administrative control over these islands. Meanwhile, the Abe administration has started considering the possibility of acquiring strike capabilities after the suspension of the Aegis Ashore ballistic missile defense system – signalling the possibility of a major break from Japan’s alleged “pacifist” national strategy since 1945.

At the same time, the move also raises questions about understanding Japan’s defense debates solely on a narrow pacifism. The idea of “maritime realism” rather than pacifism, offers a more coherent framework of Japan’s postwar foreign policy by emphasizing Japan’s mercantile approach for access to vital sea routes for trade. As an archipelago island state, Japan is in a unique geographical position since the sea has functioned as a natural barrier against invasion. It has allowed Japan to maintain a minimalist national security approach since access to sea lanes were relatively secure during the Cold War. Japan’s defense posture during this time assumed Soviet aggression from the north instead of naval rivalry in the southern seas which are more relevant to Japan’s mercantile-based policy. It is when access to these sea lanes are jeopardized that Japan embraces military power as a crucial component of its national strategy. 

It is when access to sea lanes are jeopardized that Japan embraces military power as a crucial component of its national strategy

Japan’s security policy is unique given that its constitution outlaws the use of force to resolve interstate conflicts. Legal restrictions around the application of military power have not only complicated Japan’s defense policy-making but has also made pacifism the prevailing narrative. Discussions around Japanese security policy have often been centered first on a strategy’s constitutionality rather than its security utility.

It is, however, unhelpful to mix Japan’s pacifism with Tokyo’s mercantile-based national strategy. Postwar Japan’s geoeconomic national strategy approach was devised to focus on economic prosperity while eschewing large military expenditures by relying on its alliance with the United States. Commonly known as the Yoshida Doctrine, named after Prime Minister Yoshida Shigeru, one of the main architects of postwar Japan’s national strategy, it became closely associated with pacifism since it deemphasized military force as a component of national power. Japan was able to avoid embracing military power during the Cold War conflict between the United States and Soviet Union, which allowed Japan to remain a reactive player in international security. The Yoshida Doctrine was, in fact, very much a product of U.S. strategy in the early Cold War – it capitalized on both the initial reforms aimed at democratizing Japan and the emphasis on economic statecraft as a key component of the Cold War containment strategy the prevented the spread of communism abroad. Therefore, Japan’s reactive security approach during the Cold War was not due to the nation’s pacifist identity but rather, as explained by “maritime realism,” anchored on the pursuit of economic prosperity concerned around sea lines of communication.

Japan’s reactive security approach during the Cold War was due less to its pacifist identity and more on the pursuit of economic prosperity concerned around sea lines of communication

Although Japan’s mercantile-based national strategy endured until the end of the Cold War, Tokyo faced a new strategic environment from China’s naval expansion into the maritime domain gradually leading to the current territorial waters dispute as well as a growing naval imbalance between Japan and China. Japan’s national strategy has remained consistent since the Cold War, but the only difference is the territorial dispute has propelled Japan to embrace military power—namely naval power in this case—to further pursue this national strategy. 

Whether Japan could emerge from this pandemic from an advantageous position will depend on Tokyo’s ability to continue to develop and adapt its “maritime realist” approach as access to the seas and economic resilience becomes a major theater of great power rivalry in the post-pandemic world.

Takuya Matsuda is a PhD. candidate in War Studies at King’s College London, specializing in great power relations, alliance politics, U.S. grand strategy and security affairs in the Indo-Pacific. Takuya’s work has been published by the Australian Journal of International Affairs, as well as by policy outlets such as the War on the Rocks, Foreign Policy, the National Interest, the Diplomat and the Asan Forum. He received his M.A. from Johns Hopkins University’s School of Advanced International Studies (SAIS) and his B.A. from Keio University in Tokyo, Japan.

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